Advanced digital devices (e.g., smart phones, PDAs) implement notification windows for showing the user about updated events, current statements, incoming phone calls, newly received data, etc.
For example, when a smart phone is wireless connected (e.g., over Wi-Fi) with a stand-alone camera, the user can manipulate the camera to capture images/videos, and the images/videos can be dynamically transmitted to the smart phone. It is better to show the user about the updates of incoming images/videos. However, the always-on Wi-Fi connection for transmitting the images/videos consumes a lot of energy. In addition, if the notification occurs every time when one new image/video is received, the user will receive too many notifications. The notifications frequently show-up are annoying and fail to provide further information between the incoming images/videos.